Re-recognize early recurrence of persistent atrial fibrillation.

Aims: Few studies on early recurrence (ER) focused on patients with persistent atrial fibrillation (AF). We aimed to investigate the characteristics and clinical significance of ER in patients with persistent AF after catheter ablation (CA).

Methods: A total of 348 consecutive patients who underwent first-time CA for persistent and long-standing persistent AF between January 2019 and May 2022 were investigated.

Novel monolithic catalysts for VOCs removal: A review on preparation, carrier and energy supply.

Volatile organic compounds (VOCs) are considered the culprit of secondary air pollution such as ozone, secondary organic aerosols, and photochemical smog. Among various technologies, catalytic oxidation is considered a promising method for the post-treatment of VOCs. Researchers are sparing no effort to develop novel catalysts to meet the requirements of the catalytic process.

Acid Etching-Induced In Situ Growth of λ-MnO over CoMn Spinel for Low-Temperature Volatile Organic Compound Oxidation.

Surface lattice oxygen is crucial to the degradation of volatile organic compounds (VOCs) over transition metal oxides according to the Mars-van Krevelen mechanism. Herein, λ-MnO in situ grown on the surface of CoMn spinel was prepared by acid etching of corresponding spinel catalysts (CoMn-H-T) for VOC oxidation. Experimental and relevant theoretical exploration revealed that acid etching on the CoMn spinel surface could decrease the electron cloud density around the O atom and weaken the adjacent Mn-O bond due to the fracture of the surface Co-O bond, facilitating electron transfer and subsequently the activation of surface lattice oxygen.

Recent Advances of Chlorinated Volatile Organic Compounds' Oxidation Catalyzed by Multiple Catalysts: Reasonable Adjustment of Acidity and Redox Properties.

The severe hazard of chlorinated volatile organic compounds (CVOCs) to human health and the natural environment makes their abatement technology a key topic of global environmental research. Due to the existence of Cl, the byproducts of CVOCs in the catalytic combustion process are complex and toxic, and the possible generation of dioxin becomes a potential risk to the environment. Well-qualified CVOC catalysts should process favorable low-temperature catalytic oxidation ability, excellent selectivity, and good resistance to poisoning, which are governed by the reasonable adjustment of acidity and redox properties.

Defective Ultrafine MnO Nanoparticles Confined within a Carbon Matrix for Low-Temperature Oxidation of Volatile Organic Compounds.

The development of catalysts for volatile organic compound (VOC) treatment by catalytic oxidation is of great significance to improve the atmospheric environment. Size-effect and oxygen vacancy engineering are effective strategies for designing high-efficiency heterogeneous catalysts. Herein, we explored the in situ carbon-confinement-oxidation method to synthesize ultrafine MnO nanoparticles with adequately exposed defects.

Synthesis of Silanol-Rich MCM-48 with Mixed Surfactants and Their Application in Acetone Adsorption: Equilibrium, Kinetic, and Thermodynamic Studies.

Mesoporous silica MCM-48 with rich silanol was prepared using polyvinylpyrrolidone (PVP) and cetyltrimethylammonium bromide (CTAB) as mixed templates, and the dynamic adsorption performance of acetone was evaluated by testing breakthrough curves. The mixed micelle formed by CTAB and PVP, as well as the hydrogen bond between the carbonyl group of PVP and silanol group affected the condensation process of Si-OH group during the formation of mesoporous structure, resulting in the increase of Si-OH group number on the surface of MCM-48. Compared with MCM-48 synthesized by single template (CTAB), the acetone adsorption capacity of MCM-48 (1:3) synthesized by mixed templates (PVP:CTAB = 1:3) improved by 23.

Oxidation of acetone over Co-based catalysts derived from hierarchical layer hydrotalcite: Influence of Co/Al molar ratios and calcination temperatures.

In order to enhance catalytic performance for acetone, Co-based catalysts prepared under different Co/Al molar ratios and calcination temperatures have been studied in this work. The results indicated that the catalytic activities of the catalysts firstly increased and then decreased with the increase of the Co/Al molar ratio and decreased with the increase of the calcination temperature. Based on the catalytic activities, TG/DTA, XRD, TPR and XPS characterization results, it can be found that catalytic activities of the catalysts with various Co/Al molar ratios were effected by the good crystallization structure of catalyst precursor, surface Co/Co molar ratio, low temperature reducibility, and O/O molar ratio of the catalysts.

Contamination source apportionment and health risk assessment of heavy metals in soil around municipal solid waste incinerator: A case study in North China.

Few studies have comprehensively taken into account the source apportionment and human health risk of soil heavy metals in the vicinity of municipal solid waste incinerator (MSWI) in high population density area. In this study, 8 elements (Cr, Pb, Cu, Ni, Zn, Cd, Hg, and As) in fly ash, soil samples from different functional areas and vegetables collected surrounding the MSWI in North China were determined. The single pollution index, integrated Nemerow pollution index, principal component analysis (PCA), absolute principle component score-multiple linear regression (APCS-MLR) model and dose-response model were used in this study.